The Springs Fire had burned more than 28,000 acres of rugged, brush-covered terrain by late afternoon and was 20% contained, the state's fire agency reported.

Forecasters said a weekend of increased humidity should help teams fighting the early-season blaze make gains Saturday.

"It's a total turnaround from what we had," said Kurt Kaplan, a meteorologist at the National Weather Service in Oxnard. "It should be a much better day for firefighters tomorrow."

At midday Friday, the temperature hit a record 96 in Camarillo, where the blaze began, about 50 miles north of Los Angeles.

Thousands of residents had already evacuated the Ventura County fire, including 118 families ordered from a premier Navy base because of heavy smoke after flames jumped the scenic highway.

The fire began Thursday during the morning rush hour near U.S. 101, which is the major commuter route into Los Angeles' San Fernando Valley. After reaching the coast overnight, the fire headed back inland Friday.

The fire had damaged 15 homes and destroyed at least 25 outbuildings and other property by midday. Large animals and livestock were being taken to the county fairgrounds.

No operations were affected Friday morning at the sprawling Naval Base Ventura County, which was already operating on an "essential mission" basis. The base has a population of more than 19,000 personnel and operates two runways, a sea-test range and deep-water port.

The evacuation order only affected the San Miguel housing unit for the Point Mugu air station. "This is due to smoke, rather than fire, concerns," public affairs officer Kimberly Gearhart announced on the base's Facebook page.

Tom Kruschke, Ventura County fire spokesman, said there is effectively a vast field of coals behind the flaming edges of the wildfire that could flare up when winds return.

"We're going to be at Mother Nature's mercy," Kruschke said.

He said high winds, high temperatures, low humidity, plus dry vegetation from the winter drought "adds up to a perfect storm for wildfire.''

California State University-Channel Islands, a school with nearly 5,000 students that opened in 2002, was evacuated. The Ventura County Fire Department said it had sent 20 fire engines to protect campus buildings and apartments on the eastern edge of the university.

Late Friday afternoon, residents were allowed back on campus, the Ventura County Sheriff's Office said.

Kruschke said that when firefighters first responded, the blaze was confined to 1 acre of brush by U.S. 101, near Thousand Oaks and Camarillo Springs, but that it quickly expanded because of dry weather, high temperatures and winds gusting up to 50 mph.

The cause of the fire is under investigation, he said.

State officials closed a 10-mile section of the Pacific Coast Highway between Las Posas Road in Ventura County and the Los Angeles County border because of the advancing flames.

More than 900 firefighters were battling the blaze. Earlier, TV news helicopter video showed burning recreational vehicles parked at a storage facility. Separately, a farm equipment complex went up in flames, triggering small fireballs as the blaze engulfed containers of pesticides.

Ken Pimlott, director of the state Department of Forestry and Fire Protection, known as CalFire, said conditions are unusually dry for this time of year and create an environment in which fire, once triggered, spreads rapidly. He said much of California is experiencing dry conditions not normally seen until summer.

"The faucet just turned on with fire activity,'' he said in an interview. "We're going into a fire season in the beginning of May, with conditions we would normally see in mid- to late June.''

CalFire moved crews through the night, some to fires in Northern California and others into position around the Los Angeles area, he said.

A brush fire that erupted about noon PT Friday forced a 30-minute closure of eastbound Interstate 10 near Redlands, east of Los Angeles. Air support was called in to aid firefighters on the ground. About 20 acres of hillside had burned before crews got the upper hand after about 90 minutes.

About three hours later, a brush fire in Glendale forced some evacuations and the closure of a freeway exchange, the Los Angeles Fire Department said. Helicopter and ground crews were battling flames in the hills of Chevy Chase, near the 134 Freeway.

A fire that broke out Wednesday near Banning in Riverside County was 40% contained by Thursday, with nearly 3,000 acres burned, CalFire said. Several fires were burning in the northern part of the state, including a blaze in Tehama County that had burned 2,000 acres and was only 10% contained, according to the department.